A comparison of the efficacy, safety, and longevity of two different hyaluronic acid dermal fillers in the treatment of severe nasolabial folds: a multicenter, prospective, randomized, controlled, single-blind, within-subject study.
Goodman GJ, Bekhor P, Rich M, Rosen RH, Halstead MB, Rogers JD. Clin Cosmet Investig Dermatol. 2011; 4:197-205. Epub 2011 Dec 20.